A conventional optical semiconductor device is formed into a module by telescopically inserting it into a housing. Therefore, in order to adjust the axial position of the optical semiconductor device within the housing, washer-like spacers must be placed in the housing. This adjustment of the axial position of the semiconductor device is necessary in order to adjust the sensitivity of the optical semiconductor device module. For that purpose, the number of the spacers inserted between the housing inner surface and the optical semiconductor device is adjusted to change the axial position of the semiconductor device, while monitoring its sensitivity, during the fabrication of an optical semiconductor device module. Accordingly, fabrication of optical semiconductor modules has been a troublesome work.
Japanese Published Patent Application No. SHO 60-216315 discloses an assembly in which optical elements including an optical-fiber holder, a columnar rod-lens and a reflector mirror are housed in a cylindrical container. These optical elements are fixed in position in the container by means of a threaded lid that is screwed into an open end of the container with a corresponding thread formed on its inside surface. The assembly disclosed in this Japanese patent publication includes means for pressing the optical elements into the container for fixing them in position, but not to adjust the axial position of the elements.
Japanese Published Patent Application No. SHO 63-169604 discloses a connection of an optical fiber to an optical link by engaging a thread on the cladding of the optical fiber with a thread formed in the inner surface of a connector-terminal element provided in the optical link. The object of the invention of this publication, however, is to connect the optical fiber with a light emitting or light receiving element, keeping them in mechanical, intimate contact with each other, and not the distance of the light emitting or light receiving element from the optical fiber.